This invention relates to suction cleaners (“vacuum cleaners”).
So-called “wet or dry” suction cleaners are known, being capable of sucking up solid matter in the manner of conventional suction cleaners, and, when required, liquids such as spillages of water or other liquids. Such cleaners generally incorporate a dust receptacle in the form of a tank. The suction airflow containing the solid or liquid matter which has been sucked up is led into the tank in such a way that any liquid in such air flow is deposited in the tank before the airflow reaches the cleaner's source of suction. If solid matter is to be sucked up, either a dust-filtering and retaining bag is disposed in the tank with the airflow passing through it, or, alternatively, a filter is provided at the exit from the tank leading to the source of suction, so that dry matter separated from the suction airstream by the filter is collected in the tank. Whilst such machines are effective, they may require some adaptation of the cleaner to be carried out by the user depending on whether wet or dry matter is to be sucked up, which is inconvenient. When used in “wet” mode, such a cleaner is also usable for carpet or other surface cleaning, being provided in this case with a tank for cleaning liquid e.g. a solution of a suitable detergent-type substance in water, which is delivered to a cleaning head which also provides for the suction extraction of dirty such liquid from the surface being cleaned.
Another disadvantage of such cleaners when used in the “dry” mode is that accumulation of separated dust in the material of a bag or on a filter can lead to a rapid loss of the suction power of the cleaner.
It is broadly the object of the present invention to address such problems associated with known wet or dry suction cleaners.